Mendez M V, Raffetto J D, Phillips T, Menzoian J O, Park H Y
Boston University Medical Center, Boston University School of Medicine, Massachusetts 02118, USA.
J Vasc Surg. 1999 Oct;30(4):734-43. doi: 10.1016/s0741-5214(99)70113-8.
We have previously shown that fibroblasts cultured from venous ulcers display characteristics of senescence and have reduced growth rates. Susceptibility of young fibroblasts to the microcirculatory changes associated with venous ulcers, such as macrophage trapping and activation, could explain the prevalence of senescent fibroblasts in these wounds.
We tested the in vitro effect of venous ulcer wound fluid (VUWF), as well as pro-inflammatory cytokines known to be present in VUWF (TNF-alpha, IL-1beta, and TGF-beta1), on neonatal foreskin fibroblasts (NFFs). NFF growth rates, cellular morphology, and senescence-associated beta-galactosidase (SA-beta-Gal) activity were determined in the presence or absence of VUWF and the above cytokines. VUWF TNF-alpha concentration and the effect of anti-TNF-alpha antibody on VUWF inhibitory activity were determined in samples obtained from four patients with venous ulcers.
NFF growth rates were significantly reduced by VUWF (42,727 +/- 6301 vs 3902 +/- 2191 P =. 006). TNF-alpha also significantly reduced NFF growth rates in a dose-dependent manner (P =.01). No significant growth-inhibitory activity was seen for IL-1alpha or TGF-beta. Incubation with VUWF significantly increased the percentage of SA-beta-Gal-positive fibroblasts in vitro on culture day 12 (P =.02). TNF-alpha and TGF-beta1 had similar effects. TNF-alpha was detected in all VUWF tested, with a mean of 254 +/- 19 pg/mL.
These data suggest that the venous ulcer microenvironment adversely affects young, rapidly proliferating fibroblasts such as NFFs and induces fibroblast senescence. Pro-inflammatory cytokines such as TNF-alpha and TGF-beta1 might be involved in this process. The role of other unknown inhibitory mediators, as well as pro-inflammatory cytokines, in venous ulcer development and impaired healing must be considered.
我们之前已经表明，从静脉溃疡中培养的成纤维细胞表现出衰老特征且生长速率降低。年轻成纤维细胞对与静脉溃疡相关的微循环变化（如巨噬细胞捕获和激活）的易感性，可能解释了这些伤口中衰老成纤维细胞的普遍存在。
我们测试了静脉溃疡伤口液（VUWF）以及已知存在于 VUWF 中的促炎细胞因子（肿瘤坏死因子-α、白细胞介素-1β和转化生长因子-β1）对新生儿包皮成纤维细胞（NFFs）的体外作用。在存在或不存在 VUWF 和上述细胞因子的情况下，测定 NFF 的生长速率、细胞形态以及衰老相关β-半乳糖苷酶（SA-β-Gal）活性。在从四名静脉溃疡患者获得的样本中，测定 VUWF 肿瘤坏死因子-α浓度以及抗肿瘤坏死因子-α抗体对 VUWF 抑制活性的影响。
VUWF 显著降低了 NFF 的生长速率（42,727 ± 6301 对 3902 ± 2191，P =.006）。肿瘤坏死因子-α也以剂量依赖性方式显著降低了 NFF 的生长速率（P =.01）。白细胞介素-1α或转化生长因子-β未观察到显著的生长抑制活性。在培养第 12 天，与 VUWF 孵育显著增加了体外 SA-β-Gal 阳性成纤维细胞的百分比（P =.02）。肿瘤坏死因子-α和转化生长因子-β1 有类似作用。在所有测试的 VUWF 中均检测到肿瘤坏死因子-α，平均值为 254 ± 19 pg/mL。
这些数据表明，静脉溃疡微环境对年轻、快速增殖的成纤维细胞（如 NFFs）产生不利影响，并诱导成纤维细胞衰老。促炎细胞因子如肿瘤坏死因子-α和转化生长因子-β1 可能参与了这一过程。必须考虑其他未知抑制介质以及促炎细胞因子在静脉溃疡发展和愈合受损中的作用。
